It has been reported that as positive ions in the air are increased by the effect of acid rain and exhaust gas resulting from the daily activities in cities, negative ions decrease and the environment and the living of human beings, animals, and plants may thus be deteriorated. It is also known that the increase of positive ions greater than negative ions may accelerate oxidizing corrosion, vital fault, and aging. In addition, the living creatures and water may slowly be acidified. As negative ions are generated for compensating the shortage, their abundance can reduce the weak acids to neutrals. Negative ions are commonly generated in the woods, the falls, and the seasides and their advantage is used for sedation and refreshment.
There are minerals including tourmaline, and Bakuhan stone, mottled stone for generating negative ions in the natural world. Such a mineral is milled to a powder form which is then solidified with a resin material to have a negative ion generating medium (for example, as denoted in Japanese Patent Laid-open Publication 2001-161414 or 2001-295105). Also, a fabric for generating negative ions is disclosed (for example, as denoted in Japanese Patent Laid-open Publication 2001-2888679). Moreover, proposed are air conditioners and air cleaners which can generate negative ions through electrical discharging.
However, the conventional negative ion generating mediums disclosed in the publications 2001-161414 and 2001-295105 employ simply a powder form of minerals which can generate a small but not large number of negative ions. Also, the other prior arts for generating negative ions through the electrical discharging action are bulky in the size and not simple in the construction, hence increasing the overall cost of production.
It is thus an object of the present invention to provide a negative ion generating medium which is manufactured from a mother material made of aluminum or its alloy thus decreasing the cost while generating a large number of negative ions.
It is another object of the present invention to provide a method of manufacturing a negative ion generating medium from a mother material of aluminum or its alloy for generating negative ions.
It is a further object of the present invention to provide a method of manufacturing a negative ion generating medium from a mother material surface finished by a simple manner for providing an anti-bacterial property and a deodorant property.